Flow control device for storage bins



Jan. 30, 1968 B. NEWCOMB 3,366,283

FLOW CONTROL DEVICE FOR STORAGE BINS Filed Aug. 31, 1965 /Z 61/421555 NEH/60MB I /4 mw United States Patent l 3,366,283 FLOW C(JNTROL DEVICE FUR STORAGE BINS Charles B. Newcornb, RR. 1, Brandon, S. Dak. 57005 Filed Aug. 31, 1965, Ser. No. 483,955 4 Claims. (Cl. 222196) This invention relates to a device for controlling the flow of free flowing particulate material, such as grain or feed, from grain elevators or bins, and more particularly relates to a device which prevents bridging and segregation of such material.

Storage bins or grain elevators which are substantially square or round in cross-section and which are relatively high in relation to their cross-sectional dimensions, have been found to be an efiicient storing method for free flowing particulate material. Permanent bins are frequently constructed from concrete and are four sided with a four sided hopper constructed of concrete at the discharge point of the bin. Typical hoppers have sides sloping and converging at a throat to which a gate is attached. From the standpoint of saving space at the bottom of the bin, it is most economical to make the hopper bottom with symmetrical sloping sides.

However, from the standpoint of producing instantaneous and continuous flow of feed through the gate at the throat of the hopper, this four sided, symmetrical hopper is undesirable because of the propensity of the feed to bridge and thereby terminate the downward flow of feed. Bridging may be alleviated by using a non-symmetrical hopper with two sloping sides and two substantially straight sides. This, however, results in a space problem at the bottom of the bin and considerably higher cost in producing a non-symmetrical hopper. An additional etfect of a non-symmetrical hopper is that segregation of material stored within the bin is considerably decreased.

With these comments in mind it is to the elimination of these and other disadvantages to which the present invention is directed along with the inclusion therein of other novel and desirable features.

An object of my invention is the provision of a new and improved device for preventing segregation and bridging of free flowing particulate material in a bin. The device is of simple and inexpensive construction and operation.

Another object of my invention is the provision of a device with a minimum of wearing parts and with virtually no maintenance necessary.

It is a further object of my invention to provide an item which utilizes a minimum of storage space within the bin thereby adding to the storage capacity of the bin.

A further object of my invention is the provision of a self-adjusting device which aids in preventing segregation and eliminates bridging.

These and other objects and advantages of my invention will more fully appear in the following description made in connection with the accompanying drawings wherein like reference characters refer to the same or similar parts throughout the several views, and in which:

FIG. 1 is a perspective view of the bin, broken away to show the flow control device suspended in the bin.

FIG. 2 is a plan view of the flow control device in operating position.

FIG. 3 is a longitudinal section view showing the flow control device suspended in a bin after the bin has been filled, but prior to discharge.

FIG. 4 is a plan view showing a position of the flow control device during flow of particulate material from the bin.

3,366,283 Patented Jan. 30, 1%68 FIG. 5 is a longitudinal section showing the position of the flow control device at a stage of flow of particulate material from the bin.

One form of the invention is shown in the drawings and is described herein.

A bin is shown in FIG. 1 and is indicated in general by numeral 10. The bin shown is a four-sided longitudinal bin constructed from concrete. The bin includes four walls 10a, 10b, 10c and 10d connected in series along their longitudinal sides. The walls of bin 10 form a continuous upper edge 11 which defines an opening for loading the hopper and which edge may support a bin cover if desired. A symmetrical hopper 12 having sloping walls 12a, 12b, 12c and 12d is connected to bin 10 at walls 10a, 10b, 10c and 19d respectively. Hopper walls 12a, 12b, 12c and 12d are disposed downwardly and converge at discharge throat 13 and are connected thereto. A gate 14 is connected to throat 13 and discharge from bin 10 is controlled by gate shut-off lever 14a.

The material flow control device is shown in FIG. 1 suspended in bin 10. The flow control device is shown in equilibrium position in an empty bin. The device consists of an elongated rigid trough-shaped material flow control element 15 suspended substantially upright and generally axially of the bin. A portion of control element 15 projects in throat 13. Control element 15 is typically formed from fiat steel plate stock of about /8" x 3'0 x 8'0". High carbon steel may be used for control elements placed in a bin storing highly abrasive particulate matter. In one working embodiment, control element 15 may be folded longitudinally, forming legs disposed at substantially right angles, each leg having a size of approximately X 18" X 8'0".

Chain receiving bars 16 are welded to the legs of control element 15 at the upper edge thereof. The bars 16 are located midway of the width of the leg to facilitate suspending the control element substantially upright. A chain 17 joins bar 16 to chain hanger 18, disposed on the top edge 11 of bin 10. The chain 17 is typically a heavy link chain of high tensile strength to withstand the pressures exerted by the load in a bin on the suspended control element 15. The chain 17 may also be of high carbon steel to prevent wear. The chain hangers 18, shown in FIG. 1, may be fabricated from medium web channel iron welded at a width suitable to fit over the edge 11 of bin 10 and be movable thereon. This adjustment aids in determining the equilibrium point of control element 15, freely suspending material control element 15 in throat 13. Chain hangers 18 are shown on bin walls 10a and 10c, suspending legs of control element 15 substantially parallel to walls and 10d. In FIG. 2 the flow control device is upright and is shown in a bin which is indicated as empty. The control element 15 is centrally located in the bin and disposed within throat 13. Hangers 18 are shown on the upper edge of bin walls 10a and 100.

In FIG. 3 the bin 10 is filled with material, indicated in general by numeral 19, having an apex of material, indicated in general by numeral 20. Apex 20 is present in the bin 10 only prior to discharge of any material from the bin 10 through throat 13.

FIG. 5 shows material 19 after discharge through throat 13 has begun. As shown at point 21 the material no longer has a cone with an apex as in FIG. 3, but has an inverted cone configuration with the low point located axially of the bin 10. Material flow control element 15 is shown in the position taken after flow through throat 13 has begun. The pressures from the material 19 flowing through throat 13 raise control element 15 from throat 13, and dispose it over throat 13 in a position leaning against bin walls 100 and 19d, the legs of control element 15 in contact with walls 190 and 16d respectively, and the longitudinal joint of the legs facing upwardly. This position is shown in FIG. 4. In this view material is not shown, for purposes of clarity, although the flow control device 15 is shown substantially as it appears when material is flowing through throat 13. After most of the material is discharged from the bin, material control element 15 resumes its equilibrium position as shown in FIG. 2.

In operation, the flow control device of my invention is installed in a bin by placing hangers 18 over bin wall edge 11 and moving the hangers along continuous edge 11 to a position which allows control element 15 to be suspended substantially upright, centrally located within the bin and in throat 13 without binding in throat 13. The chains 17 are of sufficient length to allow control element 15 to be disposed a short distance into the depth of throat 13.

As free flowing particulate material is discharged, typically from a belt conveyor, through the top of bin apex 26 is formed, centrally of the bin, and progresses upwardly as discharge continues. Small particles remain at the apex 20, since they do not have energy to roll down the cone shaped pile of material. Large particles of material, with suflicient energy, roll to the circumferential area of the bin. Consequently, a core of fine material is formed axially of the bin. It is this core of fine material which typically causes bridging, since initial flow is from this core area. After sufiicient flow of core material has taken place to effect the funnel 21 in material 19, an integrated mix results.

The flow control device of my invention is most useful during the initial stages of flow of feed from the storage bin. During the loading cycle of the storage bin, control element is substantially upright, and located centrally within the bin. Much of the material loaded within the bin reacts as in a hopper with two sloping sides and two straight sides. As a result material with suflicient energy does not roll past the two sides of the hopper which are substantially upright. This results in a core of material which is integrated extending from the throat to the uppermost portion of the control element 15. As material flows from the bin the material reacts as in a hopper with two sloping sides and two substantially straight sides. It is felt that the material flow is substantially the same as flow from a nonsymmetrical hopper having hopper walls at varying angles.

Since bridging occurs when the material stored within the bin develops suflicient structural strength from coacting with hopper Walls, material which reacts as in a hopper with walls of varying slopes does not readily bridge. It is felt the material flow control device of my invention simulates a hopper having two upright walls and two sloping walls converging at a throat. Consequently, the desired flow characteristics are obtained without sacrificing storage space and without sacrificing valuable head room at the hopper.

It has been found that approximately 8 feet is suflicient longitudinal dimension for the control element 15 in typical installations. This gives consistent uniform flow as well as reventing bridging. If bridging is the only problem, a shorter control element may be used. The optimum width of the control element 15 is slightly less than the width of the throat 13.

It is felt that during discharge of the material from the storage bin the freely flowing material creates a low pressure area along the joint or convex surface of the flow control element 15 such that the freely suspended control element 15 raises from the throat 13 and becomes disposed over the discharge throat 13, leaning against the walls of the bin 10. This, however, does not destroy the effectiveness of flow control 15 in that a steep sloping wall is still presented to the material at the point of discharge and therefore a stable dome is not allowed to form. After suflicient flow has taken place and the pressures created on the flow control element 15 by the material within the bin have neutralized, the control element returns to its upright position, and is ready to receive additional material to be loaded from the upper opening of the storage bin.

It will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the various parts without departing from the scope of this invention.

What is claimed is:

1. A device for preventing bridging in a bin used for storing free flowing particulate matter, the bin including an upper inlet portion and a lower end with sloped wall portions funneling the particulate matter toward the discharge throat, said device comprising,

an elongate, rigid, trough-shaped, material flow control element adapted to be suspended in the bin in a substantially upright equilibrium position, said flow control element extending downwardly partially into the discharge throat of the bin, the opposite sides of the trough-shaped control element lying adjacent the periphery of the discharge throat and also confronting the sloped wall portions of the bin and cooperating therewith in defining a bin discharge portion wherein the particulate matter flows into the discharge throat with substanitally the same flow characteristics as from a bin having a hopper with upright and sloped walls confronting each other and converging downwardly to the discharge throat,

and means swingably suspending said material flow control element in the bin.

2. A device for preventing bridging and segregation in a bin used for storing free flowing particulate matter, the bin including an upper inlet portion and a lower hopper portion with walls converging to a discharge throat, said device comprising,

a material flow control element adapted to be suspended in the bin and having a substantially upright equilibrium position, said flow control element including two elongate sides joined in substantially right angular relation along longitudinal sides thereof forming a convex outer surface and a concave inner surface, said control element partially inserted in the discharge throat of the bin and extending upwardly therefrom thereby substantially forming a bin discharge portion communicating with the lower discharge throat of the bin having two substantially upright walls two of said bin walls converging toward the discharge throat whereby material flowing from the bin discharge portion flows with substantially the same flow characteristics as material flowing from a bin having a hopper with two upright sides and two sloped sides forming the bin discharge portion and converging at the bin discharge throat, and

means suspending said material flow control element substantially upright in the bin.

3. The invention set forth in claim 2 wherein the suspending means for said material flow control element comprises a chain of predetermined length connected to the transverse upper edge of each elongate side of said flow control element, said chain connected to bin chain hangers adapted to be affixed to the upper bin inlet portion.

4. In a bin for storage of free flowing particulate matter, the bin including an upper inlet portion and a lower symmetrical hopper portion with walls converging at a discharge throat, a device for preventing bridging and segregation of material stored within the bin, said device comprising,

a material flow control element suspended in said bin in a substantially upright equilibrium position, said flow control element including elongate sides joined in substantially right angular relation along longitudi- 6 nal sides thereof forming a convex outer surface and References Cited a concave inner surface, said control element par- UNITED STATES PATENTS tlally inserted in the dlscharge throat of said bin and projecting upwardly therefrom thereby substantially 1,775,719 9/1930 ciermcflt 222 526 X forming a hopper having two substantially upright 5 2,180,468 11/1939 hochslm 222549 X Walls and two walls converging toward the discharge 337L297 1/1963 Lee 222462 throat whereby material flowing from said bin flows 3,155,293 11/1964 Cotter 222*559 X with substantially the same fl ow characteristics as FOREIGN PATENTS When flowing from a bm having a hopper with an 610,250 10/1960 Ita1y off-set discharge throat resulting in hopper walls converging at the discharged throat at varying angles, and ROBERT B REEVES Primal, Examiner means suspending said material flow control element y substantially upright in said bin. STACK, Examiner- 

1. A DEVICE FOR PREVENTING BRIDGING IN A BIN USED FOR STORING FREE FLOWING PARTICULATE MATTER, THE BIN INCLUDING AN UPPER INLET PORTION AND A LOWER END WITH SLOPED WALL PORTIONS FUNNELING THE PARTICULATE MATTER TOWARD THE DISCHARGE THROAT, SAID DEVICE COMPRISING, AN ELONGATE, RIGID, TROUGH-SHAPED, MATERIAL FLOW CONTROL ELEMENT ADAPTED TO BE SUSPENDED IN THE BIN IN A SUBSTANTIALLY UPRIGHT EQUILIBRIUM POSITION, SAID FLOW CONTROL ELEMENT EXTENDING DOWNWARDLY PARTIALLY INTO THE DISCHARGE THROAT OF THE BIN, THE OPPOSITE SIDES OF THE TROUGH-SHAPED CONTROL ELEMENT LYING ADJACENT THE PERIPHERY OF THE DISCHARGE THROAT AND ALSO CONFRONTING THE SLOPED WALL PORTIONS OF THE BIN AND COOPERATING THEREWITH IN DEFINING A BIN DISCHARGE PORTION WHEREIN THE PARTICULATE MATTER FLOW INTO THE DISCHARGE THROAT WITH SUBSTANTIALLY THE SAME FLOW CHARACTERISTICS AS FROM A BIN HAVING A HOPPER WITH UPRIGHT AND SLOPED WALLS CONFRONTING EACH OTHER AND CONVERGING DOWNWARDLY TO THE DISCHARGE THROAT, AND MEANS SWINGABLY SUSPENDING SAID MATERIAL FLOW CONTROL ELEMENT IN THE BIN. 